Objective:To investigate the impact of inserting an exogenous gene, NanoLuc (Nluc), at different sites in the influenza virus genome on viral properties and analyze the expression stability of the exogenous gene both in vitro and in vivo. Methods:Using molecular cloning techniques and reverse genetics, eight recombinant influenza viruses were constructed by inserting the exogenous Nluc gene into the gene segments encoding hemagglutinin (HA), neuraminidase (NA), non-structural protein (NS), and polymerase basic protein 1 (PB1). Viral replication capacity was evaluated by hemagglutination and plaque assays. Nluc expression in infected cells was monitored by fluorescence imaging. The potential impact of the exogenous gene insertion on viral infectivity was examined in a mouse infection model. Independent samples t-test were used for statistical analysis. Results:The recombinant viruses with insertions in the HA, NA, and NS gene segments generated fluorescent signals in the first generation of rescued viruses and demonstrated replication capabilities in plaque and hemagglutination assays. The recombinant viruses based on the NA and NS genes were capable of stably expressing Nluc across different generations, and exhibited correct fluorescent distribution patterns in mouse infection experiments. Meanwhile, the NS gene-based recombinant virus demonstrated superior stability in the mouse model.Conclusions:This study demonstrates that the NS gene segment of influenza virus can serve as an effective insertion site for exogenous genes without impairing the viral replication or infectivity, and the recombinant virus constructed based on it exhibits high integration stability and substantial application potential.

Objective:To investigate the impact of inserting an exogenous gene, NanoLuc (Nluc), at different sites in the influenza virus genome on viral properties and analyze the expression stability of the exogenous gene both in vitro and in vivo. Methods:Using molecular cloning techniques and reverse genetics, eight recombinant influenza viruses were constructed by inserting the exogenous Nluc gene into the gene segments encoding hemagglutinin (HA), neuraminidase (NA), non-structural protein (NS), and polymerase basic protein 1 (PB1). Viral replication capacity was evaluated by hemagglutination and plaque assays. Nluc expression in infected cells was monitored by fluorescence imaging. The potential impact of the exogenous gene insertion on viral infectivity was examined in a mouse infection model. Independent samples t-test were used for statistical analysis. Results:The recombinant viruses with insertions in the HA, NA, and NS gene segments generated fluorescent signals in the first generation of rescued viruses and demonstrated replication capabilities in plaque and hemagglutination assays. The recombinant viruses based on the NA and NS genes were capable of stably expressing Nluc across different generations, and exhibited correct fluorescent distribution patterns in mouse infection experiments. Meanwhile, the NS gene-based recombinant virus demonstrated superior stability in the mouse model.Conclusions:This study demonstrates that the NS gene segment of influenza virus can serve as an effective insertion site for exogenous genes without impairing the viral replication or infectivity, and the recombinant virus constructed based on it exhibits high integration stability and substantial application potential.

BACKGROUND:Most of the biomechanical studies on kyphosis have focused on trunk muscle strength and sagittal plane balance,and little has been reported on the biomechanical response within the spine during kyphosis. OBJECTIVE:To investigate the biomechanical response of the spine during postural kyphosis by simulating the process of postural kyphosis. METHODS:A three-dimensional finite element model of the normal thoracolumbar segment(T1-S1 segment)was established by using the finite element method.10 groups of pure bending loads from 1.15-11.52 N·m were applied using a three-point force system on T1,T6,and T12 vertebrae to simulate the process of postural kyphosis in normal humans.The relationship between the loads and Cobb angle and the biomechanical responses of vertebrae,ribs,and intervertebral discs were analyzed. RESULTS AND CONCLUSION:(1)During postural kyphosis,the Cobb angle size of T1-T12 segments was linearly related to the load size.(2)The maximum stresses on the vertebrae,ribs,and intervertebral discs increased with increasing load.(3)Under the action of 11.52 N·m moment,the maximum stresses on the vertebral body,ribs,and intervertebral disc were found in the front of the T6 vertebral body,the rib head of the 10th pair of ribs,and the right posterior side of the intervertebral disc of the T5-T6 segments.(4)The results of this study suggest that postural kyphosis leads to increased stress on the vertebrae,ribs,and discs,with the most significant increase in stress on the anterior side of the T6 vertebrae,at the rib head of the 10th pair of ribs,and on the anterior side of the disc at the T5-T6 segment,as well as on the posterior side,which may increase the risk of injury to the vertebrae,ribs,and discs,which provides a biomechanical basis for the design of kyphosis orthoses.

Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease (MAFLD). However, there are few reported lipotoxicity inhibitors. Here, we identified a natural anti-lipotoxicity candidate, HN-001, from the marine fungus Aspergillus sp. C1. HN-001 dose- and time- dependently reversed palmitic acid (PA)-induced hepatocyte death. This protection was associated with IRE-1α-mediated XBP-1 splicing inhibition, which resulted in suppression of XBP-1s nuclear translocation and transcriptional regulation. Knockdown of XBP-1s attenuated lipotoxicity, but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown hepatocytes. Notably, the ER stress and lipotoxicity amelioration was associated with PLA2. Both HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity, reduced lysophosphatidylcholine (LPC) level, subsequently ameliorated lipotoxicity. In contrast, overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of HN-001. Additionally, HN-001 treatment suppressed the downstream pro-apoptotic JNK pathway. In vivo, chronic administration of HN-001 (i.p.) in mice alleviated all manifestations of MAFLD, including hepatic steatosis, liver injury, inflammation, and fibrogenesis. These effects were correlated with PLA2/IRE-1α/XBP-1s axis and JNK signaling suppression. These data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity, and provide a natural structural basis for developing anti-MAFLD candidates.

Objective:To investigate the clinical characteristics of cases with different congenital pulmonary airway malformations (CPAM) volume ratios (CVR) and the effect of maternal glucocorticoid treatment during pregnancy on CPAM.Methods:A retrospective study was conducted on 56 singleton pregnant women with fetal CPAM diagnosed prenatally in the Department of Obstetrics and Gynecology at Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, from September 2020 to May 2023. Among these, three cases received maternal glucocorticoid treatment during pregnancy and clinical conditions were reported in detail. Statistical analyses were performed using independent sample t-tests, non-parametric tests, Chi-square tests, or Fisher's exact test. Results:(1) General information: The average age of the 56 pregnant women with CPAM fetuses was (32.0±0.7) years. All fetuses had unilateral lesions, with 25 cases (44.6%) on the left side. Types Ⅰ, Ⅱ, and Ⅲ CPAM accounted for 5.4% (3/56), 50.0% (28/56), and 44.6% (25/56), respectively. Fetal hydrops occurred in two cases, and the maximum CVR during the fetal period for the other 54 non-hydropic fetuses was 0.79±0.66. (2) The CVR threshold for the risk of fetal hydrops was set as the mean maximum CVR of non-hydropic CPAM fetuses plus 2 standard deviations (0.79+2×0.66=2.1). The subjects were divided into two groups based on the maximum CVR during the fetal period: CVR≤2.0 group ( n=50) and CVR>2.0 group ( n=6). Comparison between the CVR>2.0 group and CVR≤2.0 group: The CVR>2.0 group had significantly higher rates of fetal hydrops [2/6 vs. 0.0% (0/50), Fisher's exact test], mediastinal shift [5/6 vs. 32.0% (16/50), χ 2=4.03], polyhydramnios [6/6 vs. 4.0% (2/50), Fisher's exact test], and postnatal surgery [4/5 vs. 22.2% (10/45), continuity correction χ 2=4.86] (all P<0.05). None of the fetuses with CVR≤2.0 had hydrops or received intrauterine intervention. The overall live birth rate was 89.3% (50/56). (3) Maternal glucocorticoid treatment during pregnancy: three of six fetuses with CVR>2.0 were treated with maternal glucocorticoid during pregnancy, and all were delivered alive at term after the intervention with resolution of edema and/or reduction in mass size. Two of them were treated with postnatal thoracoscopic surgery and were followed up to 5 and 14 months of age, respectively, with no abnormalities in feeding and development; the other was not treated surgically until 3 months of age, with no respiratory-related symptoms and no abnormalities in feeding and development. Conclusions:Prenatal ultrasound indicating CVR>2.0 is associated with increased rates of fetal hydrops, mediastinal shift, and polyhydramnios. Maternal glucocorticoid treatment during pregnancy may lead to favorable pregnancy outcomes for these CPAM fetuses.

Objective:To investigate the feasibility of predicting the risk of spontaneous preterm birth in singleton pregnancy women with low risk of preterm birth by transabdominal-transvaginal ultrasound cervical length sequential screening in the second trimester.Methods:This prospective longitudinal cohort study included singleton pregnant women at 11-13 +6 gestational weeks who were admitted to Nanjing Drum Tower Hospital from January 2023 to September 2023. Transabdominal and transvaginal cervical lengths were measured during the mid-trimester fetal ultrasound scan at 18-24 weeks, and pregnancy outcomes were obtained after delivery. A short cervix was defined as a transvaginal cervical length of ≤25 mm, and the outcomes were defined as spontaneous preterm birth occurs between 20 and 36 +6 weeks and extremely preterm birth before 32 weeks. The area under the receiver operating characteristic (ROC) curve was used to evaluate the effectiveness of predicting spontaneous preterm birth by transabdominal and transvaginal cervix length, as well as the effectiveness of predicting short cervix by transabdominal cervical length. The relationship between transabdominal and transvaginal cervical length was evaluated using a scatter plot. Results:A total of 562 cases were included in this study, comprising 33 cases of spontaneous preterm birth (7 cases occurring before 32 weeks) and 529 cases of term birth. (1) Compared to the term birth group, transabdominal cervical length (median: 37.6 vs 33.2 mm; Z=-3.838, P<0.001) and transvaginal cervical length (median: 34.0 vs 29.9 mm, Z=-3.030, P=0.002) in the spontaneous preterm birth group were significantly shorter. (2) The areas under the ROC curve for predicting spontaneous preterm birth by transabdominal and transvaginal cervical length were 0.699 (95% CI: 0.588-0.809) and 0.657 (95% CI: 0.540-0.774), respectively. The sensitivity, specificity and positive predictive value of transvaginal cervical length Conclusions:In singleton pregnancy women with low risk of preterm birth, transabdominal-transvaginal cervical length sequential screening can reduce unnecessary transvaginal ultrasounds by approximately 41% without missing the diagnosis of pregnant women with a short cervix. This method also enhances the effectiveness of transvaginal cervical length to spontaneous preterm birth.

Objective:To explore the clinical significance of cervical length (CL) measured by transabdominal ultrasound during fetal structural anomalies screeing at 20-24 +6 weeks of gestation. Methods:This was a retrospective nested case-control study based on a prospective longitudinal cohort of "Prediction and Prevention of Early-onset Preeclampsia", which recruited 4 995 singleton pregnant women at the gestational age of 11-13 +6 weeks in Nanjing Drum Tower Hospital from April 2019 to August 2022. All the subjects underwent second-trimester ultrasound screening for fetal structural anomalies in our hospital with image records. This study excluded the women who were lost to follow-up, underwent cervical cerclage, terminated the pregnancy due to personal or social factors, or had miscarriage before 20 weeks of gestation, and those with iatrogenic preterm births, intrauterine fetal death or no second-trimester cervical sonography images. Propensity score matching was used to match pregnant women with spontaneous preterm birth ( n=101) and those with full-term delivery ( n=101) in a 1∶1 ratio, with factors of maternal age, body mass index, preterm birth history, cesarean section history, and pregnancy interval ≥5 years. CL was measured based on the retained ultrasound images. Nonparametric test or Chi-square test were used for statistical analysis. Receiver operating characteristic (ROC) curve was used to evaluate the correlation between CL measured by transabdominal ultrasound in the second trimester and spontaneous preterm birth. Results:The CL measured by transabdominal ultrasound at 20-24 +6 weeks of gestation was significantly shorter in the spontaneous preterm birth group than that in the full-term group [2.8 cm (2.5-3.3 cm) vs. 3.4 cm (3.0-3.9 cm), Z=－5.85, P<0.001]. If CL<3.4 cm was used as the cut-off value for predicting spontaneous preterm birth (20-36 +6 weeks), the specificity and the sensitivity were 0.50 and 0.77, respectively, and the sensitivity reached 0.92 for predicting preterm birth before 32 weeks and 1.00 for predicting preterm birth before 28 weeks. If CL<3.7 cm was used as the cut-off value, the specificity and the sensitivity were 0.36 and 0.87, respectively, and the sensitivity was 1.00 for predicting preterm birth before 32 weeks. The efficacy of preterm birth screening at 28-36 +6 weeks of gestation was comparable to that at 20-36 +6 weeks, if CL<3.4 cm and CL<3.7 cm were used as the cut-off value, the sensitivity were 0.76 and 0.86, respectively. Conclusion:Transabdominal ultrasound measurement of CL in the second trimester can be a preliminary screening to determine whether further transvaginal ultrasound measurement of CL is needed for women without a history of preterm birth or late spontaneous abortion.

Influenza viruses are responsible for a large number of infections and deaths annually, posing a serious threat to public health. Vaccination is the most effective measure to prevent influenza virus infection. However, current seasonal influenza vaccines only protect against closely matched circulating strains. Even with extensive surveillance and annual reformulation, yearly updated vaccines are still a step behind the fast-evolving viruses, often resulting in poor matches or less effective vaccines. Due to the relatively complex evolution of influenza A viruses, it is a new idea and a new means to prevent influenza epidemics by using a series of innovative technologies to develop universal influenza vaccines that can provide extensive and long-lasting protection against influenza viruses. This review summarized the latest progress in the development of universal vaccines targeting HA in the past three years, including design methods for universal vaccines targeting HA, HA stem and other conserved epitopes, compared the advantages and disadvantages of different technologies, explored the impact of immunization programs and strategies, and discussed the potential challenges to be overcome, hoping to provide reference for the successful development of universal vaccines.

Objective To explore the effects of attention and interpretation therapy on psycho-logical resilience,perceived stress and post-traumatic growth for postoperative chemotherapy patients with lung cancer.Methods A total of 100 postoperative lung cancer patients receiving chemotherapy were randomized into control group(n=51)and study group(n=49).The control group implemen-ted conventional psychological guidance,including affective care,psychological comfort and relaxa-tion training;the study group implemented a 10-week attention and interpretation therapy,which mainly included transcendental meditation,emotional coping,gratitude recall,individualizedpsycho-logical guidance,positive thinking training and self-acceptance.The psychological resilience scale(CD-RISC),perceived stress scale(CPSS)and post-traumatic growth inventory(PTGI)scores of the two groups were compared after the intervention.Results After intervention,the scores of all di-mensions and total scores of CD-RISC in two groups were improved compared with those before inter-vention,and were higher in the study group than the control group(P＜0.05).After intervention,the CPSS scores and total scores of two groups were lower than before intervention,and the study group was lower than the control group(P＜0.05).After intervention,PTGI scores in both groups were higher than before intervention,and the study group was higher than the control group(P＜0.05).Conclusion For postoperative chemotherapy patients with lung cancer,the psychological in-tervention of attention and interpretation therapy can effectively alleviate patients'perceptual stress,enhance their psychological resilience status,and improve level of post-traumatic growth.

Influenza viruses are common pathogens causing respiratory infections in humans. Among the four seasonal influenza viruses, influenza A virus H3N2 has become the leading cause of seasonal influenza illness and death, posing a great threat to public health and the economy. Since it first emerged and caused a pandemic in 1968, H3N2 has been circulating repeatedly in human beings and continually evades host immune attack by antigenic drift, resulting in a decrease in vaccine efficacy. In this paper, the antigenic evolution of influenza A virus H3N2, the impact of antigenic evolution on the selection of vaccine strains and some models for predicting the evolution of influenza viruses were analyzed and reviewed, which paved the road for understanding the antigenic evolution of influenza virus and vaccine development.